Artificial respiration or resuscitation techniques now being used to revive a victim without normal respiratory function involve the introduction of a fluid such as oxygen or air directly into the patient. In the most rudimentary form, this is accomplished by "mouth-to-mouth" respiration where a medical attentant or the like exhales directly into the mouth of the patient, thereby forcing air into the lungs.
A more satisfactory technique involves intubation, where a hollow tube is inserted through the mouth and into the proximity of the larynx. Yet another improvement involves sealing off the esophagus in order to prevent diversion of respiration effort to inflation of the stomach. In addition, an open esophagus can result in aspiration of the stomach contents through the esophagus into the mouth and throat, and subsequently into the respiratory passages. The occurrence of such backflow could result in the inability of the lungs to receive the fluid needed for respiration.
One prior art device is an endotracheal tube which is inserted through the mouth of the patient, through the laryngeal region and into the patient's trachea. The respirating fluid is then introduced almost directly into the lungs without significant diversion to the stomach. Insertion of the endotracheal tube requires some skill, however, and a laryngoscope is required for accurate intubation. Inserting an endotracheal tube without a laryngoscope, "blind" insertion does not always succeed and this insertion is not a technique which is recommended for use by emergency medical technicians at locations remote from a hospital.
Yet another prior art device, depicted in U.S. Pat. No. 3,683,908, embodies an esophageal obturator where an elongated tube carries an expandable device into the patient's esophagus, the expandable member to obturate, or block off, the esophagus. The elongated member includes internal openings to provide for the introduction of air into the laryngeal region. Backflow of air from the laryngeal region through the nose and mouth passages is prevented by the use of a face shield which is forced against the contours of the face to seal about the face. Such a device requires constant attendance to maintain the seal between the patient's face and the apparatus shield and, if a respirator machine is not available, two people are required to respirate the patient.
Still another prior art device is described in an article by Elam et al, Advances in Cardiopulmonary Resuscitation, 1977, pages 65-72, wherein a esophageal obturator is combined with a pharyngeal cuff to obviate the need for a sealing face mask. A pharyngeal cuff with a single tube may also be used to ventilate the laryngeal region. No attempt is made to intubate the trachea and, indeed, such intubation is taught to be undesirable.
U.S. Pat. No. 3,874,377 to Davidson discloses an insertable tube for use in sealing either the esophagus or the trachea. A rotating valve-like member permits fluid introduction through either the end of the inserted tube or at an upper location proximate to the patient's oral region. Fluid back flow is prevented by the use of a sealing face mask, as hereinabove described.
The disadvantages of the prior art are overcome by the present invention, however, and improved apparatus for emergency artificial respiration are provided for sealing the patient's airways and introducing air into the lungs.